Consumer advocate Ralph Nader told CNBC on Wednesday he thinks General Motors should hire an independent ombudsman, reporting to CEO Mary Barra, to whom engineers can report problems without fear of retaliation.
"Engineers, who know what the defects are, but are being told to shut up and get in line can complain to [this ombudsman] and they can be covered anonymously," said Nader on "Squawk on the Street." "They can be guaranteed they're not going to lose their job if they report a defect that's being covered up to the company ombudsman."
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Committees in the House and Senate are investigating why it took GM more than a decade to recall 2.6 million cars that could have faulty ignition switches and may have contributed to at least 13 deaths. The largest U.S. automaker also faces a criminal probe by the Department of Justice.
Nader, who gained attention in the mid-1960s for criticizing car companies for a lack of safety features, complained that while Barra said she learned of the defect on Jan. 31, the automaker has yet to conclude what caused the defect because its internal investigation is still underway.
In addition to hiring an ombudsman, Nader thinks its internal investigation would be expedited if GM didn't have so many layers of management that he described as a "huge mass of ambiguity."
"There's not a clear line of responsibility from the design committees to the review committees to the approval of the overall vehicle," Nader said. "This is a gigantic bureaucracy that does not ascribe specific responsibility and accountability at the get go."